AutoCodes – Cadillac – U0249 Cadillac

U0249 Cadillac Code - Lost Communication With Rear Entertainment Control Module

Quick Answer

Modules connected to the high speed General Motor Local Area Network (GMLAN) serial data circuits monitor for serial data communications during normal vehicle operation. Common causes include Faulty Rear Entertainment Control Module, Rear Entertainment Control Module harness is open or shorted, Rear Entertainment Control Module circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: U0249 Cadillac indicates Lost Communication With Rear Entertainment Control Module.
Common causes: Common causes include Faulty Rear Entertainment Control Module, Rear Entertainment Control Module harness is open or shorted, Rear Entertainment Control Module circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 765

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Apr 05, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code U0249 Cadillac Description

Modules connected to the high speed General Motor Local Area Network (GMLAN) serial data circuits monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be exchanged on the serial data circuits, for each virtual network. The messages are supervised and also, some periodic messages are used by the receiver module as an availability indication of the transmitter module. The supervision time-out period is 250 ms. Each message contains the identification number of the transmitter module. The Diagnostic Trouble Code (DTC) sets when a periodic message from the Rear Entertainment Control Module has not been received.

OBDII Code U0249 Cadillac - Lost Communication With Rear Entertainment Control Module - AutoCodes.com — U0249 Cadillac Code - Lost Communication With Rear Entertainment Control Module

What does this mean?

What are the Possible Causes of the DTC U0249 Cadillac?

Faulty Rear Entertainment Control Module
Rear Entertainment Control Module harness is open or shorted
Rear Entertainment Control Module circuit poor electrical connection

How to Fix the DTC U0249 Cadillac?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the U0249 Cadillac code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about U0249 Cadillac Code

1. What are the common symptoms of OBDII code U0249 in a Cadillac related to the Rear Entertainment Control Module?

- Common symptoms include non-functional rear entertainment system, loss of communication with the rear display, and error messages on the screen.

2. What are the possible causes of the U0249 code indicating lost communication with the Rear Entertainment Control Module in a Cadillac?

- Causes may include a faulty rear entertainment control module, wiring issues, loose connections, or a software glitch.

3. How can I diagnose the U0249 code for lost communication with the Rear Entertainment Control Module in my Cadillac?

- Diagnostic steps may involve checking the wiring connections, inspecting the control module for damage, and using a diagnostic scanner to read the error codes.

4. Can I still drive my Cadillac if the U0249 code for the Rear Entertainment Control Module communication issue is present?

- It is generally safe to drive the vehicle with this code, but the rear entertainment system may not function properly until the issue is resolved.

5. Is it possible to reset the U0249 code related to the Rear Entertainment Control Module on a Cadillac without repairing the issue?

- Resetting the code may temporarily clear the error, but it will likely reappear if the underlying communication problem is not fixed.

6. Are there any quick fixes or repair tips for resolving the U0249 code in a Cadillac with a lost communication issue in the Rear Entertainment Control Module?

- Quick fixes may include checking and securing the wiring connections, ensuring the control module is properly seated, and performing a software update if available.

7. How much does it typically cost to repair the U0249 code indicating a communication problem with the Rear Entertainment Control Module in a Cadillac?

- The cost of repair can vary depending on the exact cause of the issue, but it may range from a few hundred to a thousand dollars, including parts and labor.

8. Can a DIY enthusiast with basic automotive knowledge fix the U0249 code for lost communication with the Rear Entertainment Control Module in a Cadillac?

- DIY repair is possible for simple issues like loose connections, but more complex problems may require professional diagnosis and repair to ensure proper functioning.

9. Will ignoring the U0249 code related to the Rear Entertainment Control Module communication problem affect other systems in my Cadillac?

- Ignoring the code may only impact the rear entertainment system, but it is recommended to address the issue promptly to prevent any potential electrical problems from spreading.

10. Is the U0249 OBDII code specific to Cadillac vehicles, or can it occur in other car makes and models?

- The U0249 code indicating lost communication with the Rear Entertainment Control Module is specific to Cadillac vehicles and may not be applicable to other car brands.